PRBB Computational Genomics Seminars Amelie Baud

22/01/202612:00R_473.10_AULAPRBB Computational Genomics SeminarsAmelie BaudBaud Lab, Social and host-microbiome systems Group (CRG)"Multi-cohort analysis of host genetic effects on the gut microbiome"Host: Guigó Serra, RodericAbstract:The intestinal microbiome influences health and disease. Its composition is affected by host genetics and environmental exposures. Understanding host genetic effects is critical but challenging in humans, due to the difficulty of detecting, mapping and interpreting them. To address this, we analysed host genetic effects in four cohorts of outbred laboratory rats exposed to distinct but controlled environments. We found that polygenic host genetic effects were consistent across environments. We identified three replicated microbiome-associated loci, one of which involved a sialyltransferase gene and Paraprevotella. We found a similar association in a human cohort, between ST6GAL1 and Paraprevotella, both of which have been linked with immune and infectious diseases. Moreover, we found evidence of indirect genetic effects on microbiome phenotypes, whereby the microbiome of one animal is affected by heritable traits - hence by the genotypes - of its cagemates. Indirect genetic effects substantially increased the total genetic variance of microbiome phenotypes. Finally, we identified a novel mechanism whereby indirect genetic effects (be they on the microbiome or other phenotypes) can contribute to “missing heritability”.